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Crescimento populacional e análise isotópica de Diaphanosoma spinolosum e Ceriodaphnia cornuta (Crustacea: Cladocera), alimentadas com diferentes fra es de seston natural = Population growth and stable isotope analyses of Diaphanosoma spinolosum and Ceriodaphnia cornuta (Crustacea: Cladocera) fed with different seston size fractions
Pedro Caraballo,Andrés Felipe Sanchez-Caraballo,Bruce Forsberg,Rosseval Leite
Acta Scientiarum : Biological Sciences , 2011,
Abstract: Para definir o efeito do seston como fonte de alimento para Ceriodaphnia cornuta e Diaphanosoma spinolosum durante a enchente no lago Catalao (Amazonia Central) foram desenvolvidos experimentos gin situ h, utilizando a variacao natural de 13C e 15N comotracadores de alimento. As duas especies tiveram acesso a tres diferentes fracoes de seston (< 10, < 30 e < 60 êm) sendo mantidas em garrafas plasticas de 1,1 L submersas, durante nove dias. As atividades foram iniciadas com uma populacao de dez individuos em cada frasco, com tres frascos por cada fracao e quatro intervalos de tempo, para um total de 27 frascos por especie. A cada tres dias, foram coletados tres frascos e os organismos foram fixados para contagem e observacao de parametros populacionais. Os organismos nos ultimos tres frascos de cada fracao foram fixados com formalina e usados para analise de isotopos estaveis de carbono e nitrogenio. As duas especies cresceram em todas as fracoes de alimento, sendo melhor seu desempenho populacional na fracao < 30 êm. D. spinolosum e C. cornuta apresentaram enriquecimento nos valores de 13C e 15N, sendo maior na fracao < 10 êm. Estes resultados sugerem que as fracoes do seston testadas produzem diferentes taxas de crescimento populacional e assinaturas isotopicas nos cladoceros. In order to define the effect of seston size fraction as a food source for Ceriodaphnia cornuta and Diaphanosoma spinolosum, in situ experiments using natural abundance of 13C and 15N were carried out during the rising water period in Catalao Lake. Both species werefed with three different fractions of seston from the lake (< 10, < 30 and < 60 êm) and maintained in submerged 1.1 L plastic bottles for nine days. Ten individuals were put in each flask, maintaining three flasks for each fraction, for a total of 27 flasks per species. Every three days we collected three flasks and fixed the individuals for subsequent counting and observation of demographic population parameters. The organisms in the last three flasks of each fractionwere fixed for stable isotope analysis of 13C and 15N. Both species grew in all of the food fractions, with the best the performance coming in the < 30 êm fraction. D. spinolosum and C. cornuta showed enrichment in 13C and 15N, which was highest in the < 10 êm fraction for both species. These results show that the seston size fractions tested produce different population growth rates and isotopic signatures in cladocerans.
Toxicidad aguda y crónica del lindano sobre Ceriodaphnia cornuta (Cladocera: Daphniidae) Acute and chronic toxicity of lindane on Ceriodaphnia cornuta (Cladocera: Daphniidae)  [cached]
Jorgelina Juárez,Alcira Villagra de Gamundi
Revista Peruana de Biología , 2011,
Abstract: El lindano es un plaguicida organoclorado cuya toxicidad produce efectos nocivos en la salud humana y la biota. El objetivo de este estudio fue evaluar la toxicidad aguda y crónica del lindano sobre el microcrustáceo Ceriodaphnia cornuta. Para las pruebas agudas se empleó un dise o estático, usando 10 neonatos ≤ 24 horas de edad para el control y para cada concentración de lindano (5, 10, 15, 20 y 25 mg/L). Se realizaron tres réplicas de cada tratamiento. Se controló la inmovilización de los individuos a las 48 hs y se calcularon los valores de CL50. Los bioensayos crónicos consistieron en un dise o semi-estático, utilizando 10 neonatos menores de 24 horas de edad (uno por recipiente) para el control y para cada concentración subletal del tóxico (0,1; 0,15; 0,2; 0,25 y 0,3 mg/L). Se evaluaron los efectos sobre la supervivencia y reproducción durante 21 días. El valor obtenido de CL50 48 horas fue de 5,293 ± 0,7 mg/L. Los parámetros reproductivos (neonatos por hembra, tama o de la camada e índice de incremento natural) disminuyeron al aumentar la concentración del tóxico evaluado, mientras que el inicio de la madurez sexual se retrasó, demostrando la sensibilidad de los organismos prueba al lindano. Lindane is an organochlorine pesticide toxicity which produces harmful effects on human health and biota. The aim of this study was to evaluate the acute and chronic toxicity of Lindane on microcrustaceans Ceriodaphnia cornuta. For acute tests used a static design, using 10 infants ≤ 24 hours of age for control and each concen- tration of lindane (5, 10, 15, 20 and 25 mg/L). There were three replicates of each treatment. Monitored the detention of individuals at 48 am and calculated LC50 values. Chronic Bioassays consisted of a semi-static design, using 10 infants ≤ 24 hours of age (one per vessel) for the control and each of the toxic sublethal concentration (0.1, 0.15, 0.2, 0.25 and 0.3 mg/L). The effects on survival and reproduction over 21 days. The LC50 value of 48 hours was 5.293 ± 0.7 mg/L. Reproductive parameters (neonates per female, litter size and rate of natural increase) decreased with increasing concentration of toxic evaluated, while the onset of sexual maturity is delayed, thus demonstrating the sensitivity of test organisms to lindane.
Estudios sobre la biología y ecología de Ceriodaphnia cornuta SARS: UNA REVISIóN
Villalobos?,Mariela J; González,Ernesto J;
Interciencia , 2006,
Abstract: ceriodaphnia cornuta sars is one out of three most abundant cladocerans in tropical freshwaters, and the only one belonging to the daphniidae family. this crustacean can tolerate low concentrations of dissolved oxygen and high temperature variations, two features that allow it to be widely distributed in the tropical freshwaters. concerning feeding habits, c. cornuta prefers diatoms and green algae. this cladoceran maintains high growth rates under good-quality food conditions as well as in low-quality ones, consuming, in the last case, blue green algae. c. cornuta shows a short embryonary development, high growing rates of juveniles and early sexual maturity; it has low fecundity and high longevity. predation by fish and chaoborus sp. is an interspecific interaction that has inspired very extensive studies about this crustacean. these studies have shown important effects of predation on its abundance and distribution in freshwaters. c. cornuta may show a series of defense mechanisms as a response to predators, among which polymorphism, changes in some life-history parameters and vertical migration are well documented. all of these aspects justify the importance of c. cornuta as a key organism to obtain a better understanding of dynamics and energy transfer in tropical freshwaters.
Cladocerans (Branchiopoda) of a tropical estuary in Brazil
Paranaguá, M. N;Neumann-Leit?o, S;Nogueira-Paranhos, J. D;Silva, T. A.;Matsumura-Tundisi, T.;
Brazilian Journal of Biology , 2005, DOI: 10.1590/S1519-69842005000100015
Abstract: the study was conducted in the capibaribe river estuary in recife (brazil) to assess the role played by cladocerans in a eutrophic environment. samplings were carried out monthly at 4 fixed stations along the estuary from july 1987 to june 1988. collections were made with a plankton net of 65 micrometers mesh size. six cladocerans species were registered: penilia avirostris, diaphanosoma spinulosum, chydorus barroisi, ceriodaphnia rigaudi, ilyocryptus spinifer, and moina micrura. the most frequent species was moina micrura with 49%. the only true marine species was penilia avirostris, which was registered at station 1 (close to the river mouth), during high and low tide and in the dry season. the cladocera average density decreased from 329 ind.m-3 (august 1987, high tide) to 2 ind.m-3 (march 1988, high tide) due to the high load of organic and chemical pollution received by the estuary. at all stations, d. spinulosum, m. micrura, and c. barroisi occurred with a wide distribution, mainly during the rainy season. c. rigaudi and i. spinifer were rare, occurring only during the rainy season. cladocerans played an important role in the food webs of the plankton community of the capibaribe tropical estuary and the dominance of a few small species indicated a hypereutrophic environment. a high level of disturbance was indicated by the decline in diversity of specialized species and the increase in abundance of opportunistic species like m. micrura.
Morphological and Molecular Identification of Three Ceriodaphnia Species (Cladocera: Daphniidae) from Australia  [PDF]
Pranay Sharma
Advances in Zoology , 2014, DOI: 10.1155/2014/258134
Abstract: Australian Ceriodaphnia (Cladocera: Daphniidae) are examined using morphological attributes and two mitochondrial DNA (COI and 16s) and one nuclear DNA (28s) gene fragments to differentiate the species. The sequence data supports the existence of three species, that is, C. dubia, one reinstated species C. spinata Henry, 1919, and one new species C. sp. 1. Morphological characteristics were also able to accurately separate the three species. Furthermore, genetic analysis of COI sequences from Ceriodaphnia supported three clades. The high degree of correlation between morphological and molecular identification in this study indicates that mitochondrial markers, COI and 16s, are appropriate molecular markers for species discrimination and identification of Ceriodaphnia. 1. Introduction Ceriodaphnia Dana, 1853 (Cladocera: Daphniidae), displays little diversification in terms of species richness and morphological disparity, with the genus currently comprising 14 “valid” species worldwide, predominantly based on morphology [1]. In addition, there are 21 species inquirenda and 24 species that are probably junior synonyms of previously described species [1]. There is limited morphological and genetic evidence to support this proliferation of the large number of proposed names. According to Smirnov and Timms (1983) [2], there are only five Ceriodaphnia species from Australia which includes one beaked species (‘beak’ = a rostral projection) i.e. C. cornuta Sars, 1885, and four non-beaked species C. dubia Richard, 1894, C. laticaudata Müller, 1867, C. quadrangula (Müller, 1785) and C. rotunda Sars, 1862. One further, non-beaked species, C. pulchella Sars, 1862, has been recorded since [3]. In addition to these, two more non-beaked species, C. planifrons Smith, 1909 and C. spinata Henry, 1919 were re-instated by Berner [4], thereby increasing the total number of recorded species from Australia to eight. The literature on Ceriodaphnia sp. generally points towards the absence of divergent morphological characters for this group. Additionally, the historical taxonomic descriptions are incomplete and primarily focused on the head, antennule, antennae, postabdomen, carapace, reticulation, and rarely trunk appendages of Ceriodaphnia. Where morphological evidence is unclear, molecular techniques can be used to improve our understanding of taxonomic divergence and speciation. Barnett et al. [5] emphasised that genetics has become an increasingly important parameter in the classification and identification of organisms in comparison to more traditional morphological
Distribution and abundance of Cladocera (Branchiopoda) in the Paraíba do Sul River estuary, Rio de Janeiro, Brazil
Sterza, José Mauro;Fernandes, Luiz Loureiro;
Brazilian Journal of Oceanography , 2006, DOI: 10.1590/S1679-87592006000300003
Abstract: to characterize the cladoceran community of the paraíba do sul river estuary, located in the district of s?o jo?o da barra, rio de janeiro, brazil, cladocerans were collected monthly in nine sampling stations from september 2002 until august 2003. samples were obtained by subsurface tows using a plankton net with a 30 cm opening mouth and 70 micron mesh size, fitted with a mechanical flowmeter. environmental parameters such as salinity and temperature were also obtained. seventeen species of cladocera were identified: pseudoevadne tergestina, penilia avirostris, macrothrix triserialis, moina micrura, simocephalus kerhervei, simocephalus vetalus, simocephalus latirostris, simocephalus serrulatus, alona rectangula, alona quadrangularis, bosmina longirostris, bosminopsis deitersi, camptocercus dadayi, ceriodaphnia richardi, diaphanosoma fluviatile, kurzia latissima and pleuroxus similis. the highest total abundance of cladocera occurred in april in the marine zone of the estuary. the most abundant species during this period was penilia avirostris. at the mixing and freshwater zones of the estuary, the most abundant species were moina micrura, mainly in january; and simocephalus vetalus and bosmina longirostris during spring. from this scenario, it can be inferred that the cladoceran community of the paraíba do sul river estuary presents characteristics of marine, brackish and freshwater environments. temperature and salinity seem to limit the occurrence and distribution of cladocerans in the estuary.
Updating Anostraca (Crustacea, Branchiopoda) distribution in Italy  [cached]
Graziella MURA
Journal of Limnology , 2001, DOI: 10.4081/jlimnol.2001.45
Abstract: In this note recent records of some Anostraca species in Italy are presented. These data widen the known distribution in Italy of Branchipus schaefferi Fischer, 1834, Tanymastix stagnalis Linnaeus, 1758, Chirocephalus ruffoi Cottarelli & Mura, 1984 and Branchinella spinosa Milne-Edwards, 1840, and illustrate the problem of inadequate knowledge of our territory, at least as far as Anostraca (Branchiopoda) are concerned.
Production of Inulinases from Penicillium spinulosum, Aspergillus parasiticus NRRL2999 and Trichoderma viride  [PDF]
Figen Ertan,Filiz Ekinci,Tulin Aktac
Pakistan Journal of Biological Sciences , 2003,
Abstract: The some cultivation conditions of fungal inulinases and action of enzymes were studied in containing Jerusalem artichoke powder. The highest inulinase activity from A. parasiticus observed at 30°C, the initial pH at 5.0 and cultivation time was 24th hours. P. spinulosum inulinase activity was maximum when the cultivation time was 2 days at a temperature of 30°C with the initial pH at 5.0. The maximum inulinase activity of T. viride was determined at 25°C, the initial pH at 6.0 and cultivation time was 4 days. It was found that A. parasiticus and P. spinulosum had exoinulinase however T. viride had endoinulinase by TLC (Thin Layer Chromatography). The maximum I/S ratios for A. parasiticus, P. spinulosum and T. viride were 1.61; 1.79 and 2.6 under optimal conditions, respectively. A. parasiticus and P. spinulosum could be used as source of exoinulinase moreover T. viride could be used as source of endoinulinase.
Nuevo hallazgo de Miersia cornuta Phil. (Gilliesieae-Alliaceae)
Escobar,Inelia; Novoa,Patricio; Ruiz,Eduardo; Negritto,María; Baeza,Carlos;
Gayana. Botánica , 2010, DOI: 10.4067/S0717-66432010000100012
Abstract: a new discovery of miersia cornuta phil. from valparaiso region, chile, is presented. details of fower and fruit has been unclear, what has caused this taxon has been considered a doubtful species. the complete description, commentaries, new localities of this endemic species, and a key for miersia species are given.
Natural infection of Viola cornuta (Violaceae) with Cucumber mosaic virus, subgroup I
Arneodo,Joel; de Breuil,Soledad; Lenardon,Sergio; Conci,Luis;
Biocell , 2005,
Abstract: plants of viola cornuta displaying typical virus symptoms were observed during spring 2003 in a plant nursery in córdoba, central argentina. electron microscopic examinations of symptomatic leaf samples revealed the presence of isometric virus-like particles about 30 nm in diameter. subsequent serological analysis allowed the identification of the pathogen as a subgroup i strain of cucumber mosaic virus (cmv). these results were confirmed by antigen capture - reverse transcription - polymerase chain reaction with specific cmv primers, and digestion with a restriction enzyme. this is the first report of cmv infecting v. cornuta in argentina.
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